Answer
Domagk was a chemical tester for IG Farben, a German chemical company. In 1932, he discovered that sulfanilamide, a compound he was testing, had antibacterial properties. He tested it on mice infected with streptococci and found that it was effective in killing the bacteria. He published his findings in 1935, but they were not widely accepted until after World War II, when they were used to treat wounded soldiers.